Conventionally, in image pickup devices, if a user simply performs an operation of pressing a shutter button once, it is possible to acquire a plurality of still images whose compositions are different from each other. Hereinafter, an operation, of pressing a shutter button, which is performed by the user is referred to as a shutter pressing operation. Also, photographing which acquires a plurality of still images whose compositions are different from each other by only one shutter operation performed by the user, as described above, is referred to as composition bracket photographing.
As a conventional image pickup device that performs the composition bracket photographing, there is an image pickup device disclosed in Japanese Laid-Open Patent Publication No. 2004-109247 (patent document 1), for example. FIG. 15 is a diagram illustrating composition bracket photographing performed by the conventional image pickup device disclosed in patent document 1. In the image pickup device according to patent document 1, when the user performs a shutter pressing operation, a lens position of a zoom lens is shifted from a first position (a region R0) set by the user at a time point when the shutter pressing operation is performed to a second point (a region R1) which is positioned within an angle range wider than that of the first position. Thereafter, the image pickup device of patent document 1 photographs a wide-angle image (the region R1) by means of a CCD image pickup device. Thereafter, the image pickup device of patent document 1 extracts, as a plurality still images, a plurality of regions (the regions R0, R2) whose sizes each corresponds to an angle of view of the first position and whose positions in the photographed image (the region R1) are different from each other. Thus, the image pickup device of patent document 1 acquires a plurality of still images whose compositions are different from each other by one shutter pressing operation performed by the user.
As another conventional image pickup device that performs the composition bracket photographing, there is an image pickup device disclosed in Japanese Laid-Open Patent Publication No. 2006-211489 (patent document 2), for example. FIG. 16 is a diagram illustrating composition bracket photographing performed by a conventional image pickup device disclosed in patent document 2. In the image pickup device of patent document 2, when the user selects a zoom continuous shooting mode, a plurality of zoom continuous shooting frames are displayed as preview images together with a through image of a subject. Then, the image pickup device of patent document 2 updates preciously-stored trimming positions of the zoom continuous shooting frames in accordance with a cross-key operation performed by the user, so as to display zoom continuous frames (20a, 20b) at the most recently-stored trimming positions which have been updated. In the image pickup device of patent document 2, when the user performs the shutter pressing operation, a still image shooting processing is started, and still images acquired by the still image shooting processing are stored in a buffer memory. Then, the image pickup device of patent document 2 generates a still image included in a zoom continuous shooting frame 20a and a still image included in a zoom continuous shooting frame 20b based on the acquired still images through trimming processing, and stores both of the generated still images in the buffer memory. Thereafter, the image pickup device of patent document 2 stores still image acquired by photograph processing and the generated still images in a flash memory. Note that in the image pickup device of patent document 2, a plurality of still images acquired by executing the above processing are stored as a group of images. As such, the image pickup device of patent document 2 acquires a plurality of still images whose compositions are different from each other by one shutter pressing operation performed by the user.    [patent document 1] Japanese Laid-Open Patent Publication No. 2004-109247    [patent document 2] Japanese Laid-Open Patent Publication No. 2006-211489